ISLAMABAD, Pakistan — A wave of violence from Islamic extremists against politicians in Pakistan intensified Monday with a suicide bombing at the home of an opposition lawmaker that left at least 18 dead.

The latest attack provided a further blow to the fragile hold of democracy in key anti-terror ally Pakistan, which is struggling to cope with an Islamist insurgency and with an economic crisis that has pushed the country to the brink of bankruptcy.

Pakistan's security forces are fighting a fierce battle with Taliban militants in Bajaur, a part of its Federally Administered Tribal Area that runs along the Afghan border, and in Swat, a valley in the northwest, after a short-lived policy of seeking peace deals with the extremists collapsed.

An attacker walked into an open meeting that Member of Parliament Rashid Akbar Nowani was holding in the courtyard of his home in the central town of Bhakkar, in Punjab province, and blew himself up amid of throng of about 200. Some reports put the death toll as high as 25, while 53 were hurt, some critically. Nowani got away with minor leg injuries.

Television pictures showed bodies roughly wrapped in cloth being hurriedly taken away on beds.

Within the last week, two political leaders from Awami National Party, which leads the regional government in the insurgency-plagued North West Frontier Province, were targeted.

The assault against Nowani, who is from the conservative, mildly Islamist party of former Prime Minister Nawaz Sharif, could signal a broadening of the militants' campaign of violence. The Punjab, where Nowani is based, has so far escaped the brunt of the onslaught. There was speculation that he was attacked because he's from the minority Shiite sect of Islam, which is despised by the Taliban.

Afrasiab Khattak, a senior member of the ANP and the provincial "peace envoy", admitted that a new strategy was required to tackle the militancy flowing out of FATA.

"FATA, unfortunately, is like Afghanistan was before September 11th. It is totally controlled by militants," said Khattak. "As long as FATA is controlled by militants, it is very difficult to have stability in this province."

Thursday, the leader of the ANP, Asfandyar Wali Khan, narrowly escaped a suicide bombing at his home in NWFP which killed four, when a guard jumped on top of the attacker. Khan, along with is family, has now been forced to take refuge inside the presidential palace in Islamabad.

On Sunday, rockets were fired at the family home of NWFP chief minister Amir Haider Hoti, though no one was injured.

Late Monday, the federal government, which was elected earlier this year after more than eight years of military rule, stepped up security for politicians, restricting their movements and announcing plans to put concrete barricades outside their homes.

Last month, a truck bomb at the Marriott hotel in Islamabad killed 55 and appeared to signal a new phase in the terror campaign unleashed last summer by the Taliban and other extremist groups.

Blaming Afghan refugees for involvement in the violence, Pakistan has begun deporting thousands who had long settled in the Bajaur area back to Afghanistan.

The security crisis has pushed Pakistan into danger of default on its debt, as money has fled abroad and its currency plunged in value, hitting a new low against the dollar Monday after the rating agency Standard & Poor's downgraded the country further into junk territory.

Pakistan now has about eight weeks worth of foreign-exchange reserves left and new President Asif Ali Zardari has appealed for massive international financial support.